Captaining Gloucester for the first time, he was sent to the sin bin with London Irish hooker David Paice after they traded blows early in the second half.

As they reached the touchline they clashed again, setting off a mass brawl involving players of both sides.

London Irish director of rugby Brian Smith said: “Jim Hamilton was the instigator and when they were both yellow carded he punched David Paice twice on the head. He has concussion and a dozen stitches. Jim Hamilton has a lot to answer for.”

The Scotland player was even condemned by his own coach, Carl Hogg, after Gloucester’s 52-18 thrashing.

Hogg said: “That lack of discipline is not acceptable.”

Hamilton is likely to be dealt with severely at a disciplinary committee meeting this week.

An SRU spokesman declined to comment last night but the player seems certain to be serving a lengthy ban when Scotland leave for Australia, Fiji and Samoa on May 24.